1. Field of the Invention
The invention relates to a device for influencing reactive power flows in multi-phase alternating current and three-phase systems comprising a plurality of thyristor-controlled or thyristor-switched coil branches, in which a first coil branch is connected to a first phase and a second phase of the alternating current system and another coil branch is connected to the first phase and another phase of the alternating current system. Each coil branch comprises a first partial coil and a second partial coil, which partial coils are connected via two first network-end electrical terminals respectively to the corresponding phase of the alternating current system and via two second thyristor-end electrical terminals to a thyristor unit connected between the partial coils. Furthermore, a first partial coil and a second partial coil respectively form a structurally independent coil subassembly and the longitudinal mid-axes of each of the preferably hollow cylindrical partial coils in the coil subassembly are oriented essentially vertically with respect to a support plane, in particular the ground or a building floor.
2. Description of the Related Art
Devices for influencing reactive power flows in multi-phase, in particular three-phase, alternating current systems with a plurality of thyristor-controlled or thyristor-switched coil branches between the phases of the alternating current system are basically known and for example constitute an essential component of so-called static reactive power compensators (static var compensators, SVC) and other flexible alternating current transmission systems (FACTS).
Also known with such devices is an approach whereby the inductance of a coil branch is split uniformly between two partial coils or chokes and the thyristors are connected between these two partial coils in order to achieve improved short-circuit and earth-fault protection. In this connection, another known approach is to combine the two partial coils of a coil branch, which are of an identical design and hence more efficient to manufacture in particular, in a structurally independent coil subassembly and the partial coils are disposed one above the other, primarily for reasons pertaining to space, in which case isolator or support elements support the bottom partial coil on the bottom support plane or ground on the one hand and support the top partial coil in an isolated arrangement relative to the bottom partial coil on the other hand.